Magneto-optical observations of a second flux front, which occurs at the second peak in the magnetization of Bi_2 Sr_2 CaCu_2 O_x single crystals related to the known first order ``vortex-lattice melting'', are reconsidered. We show that, in thin samples, electrodynamics necessarily leads to an extended region in which the magnetic induction adopts a nearly constant value close to that at which the phase transition occurs at thermal equilibrium. In this region a dynamical phase mixture of vortex ``solid'' and ``liquid'' should exist. Interestingly, the observed second flux front does not mark the ``melting'' front, as it was naively interpreted earlier, but indicates the disappearance of the last ``solid droplets''.
@article{arxiv.cond-mat/0208468,
title = {"Vortex-melting front" in thin superconductors with pinning},
author = {M. V. Indenbom and E. H. Brandt and C. J. van der Beek and M. Konczykowski},
journal= {arXiv preprint arXiv:cond-mat/0208468},
year = {2007}
}
Comments
Summitted to Phys.Rev. B 8.05.2002, resubmitted 23.08.2002; 7 pages, 6 figures